The local loop of a telephone system is what some have termed the "last mile" or the "last 1000 feet". This local loop is essentially the copper wire that connects the customer premises (i.e., a house or business) to the telecommunications network. The cost of laying down the copper wire can be very expensive (ie, over $1 per foot). Where communities are rural in nature as in some parts of the United States or in developing countries, laying down such an infrastructure can be prohibitively expensive.
As an alternative to installing a wire or cable infrastructure, these rural communities are turning to wireless solutions for their telecommunication needs. However, conventional wireless telecommunication technologies suffer from a number of disadvantages. Often times, because of the quality of the service, modem connections are frequently difficult to establish and maintain. Even where modem connection are possible, data rates are often prohibitively slow.
A further disadvantage of conventional wireless telecommunication technologies relate to their inefficient use of their RF spectrum resources. Subscribers transferring data over the network occupy channels that would otherwise be available for voice communication. In instances in which many subscribers are, for example, accessing the internet, these conventional wireless technologies suffer from a serious degradation in Grade of Service (GOS) resulting in a increase in the percentage of calls blocked (i.e., Erlang B).
These deficiencies are particularly troublesome in view of the fact that data usage is bursty in nature. Analysis of internet data usage indicates that approximately 95-97% of time, the data network is idle. The aggregate throughput to a user is typically less than 5 kilobits per second.
Therefore, there is a need for a wireless telecommunication system to replace the local loop which more efficiently allocates resources between voice and data communications yet maintains a desirable high GOS. In implementing a wireless telecommunication system, it is critical that a base station be able to communicate in an efficient manner with various subscriber stations.
It is also an object of the present invention to provide a base station architecture that allows the central office and antenna to be conterminous.
It is a further object of the present invention to provide a base station architecture to remotely locate a wireless portion of a base station to be better situated in a wireless system, away from the central office.
It is a further object of the present invention to provide an internal channel concentration capability to reduce the cost and complexity of back haul to the remote base stations.
It is a further object of the present invention to provide a base station architecture that permits wired access to subscribers in one location and wireless access to subscribers in a second location.
It is a further object of the present invention to provide a base station architecture having redundancy and protection switching.
It is a further object of the present invention to provide a base station architecture having, in addition to a low tier communication service capable of providing less than 256 KBPS to the subscriber, a high tier access system such as ADSL channel banks and primary rate ISDN banks capable of providing greater than 256 KBPS access to the subscriber and multiple MBPS interfaces.
It is a further object of the invention to provide a base station system that allows individual subscribers in an area of service seamless telecommunications access (i.e., POTS (plain old telephone system), ISDN (Integrated Services Digital Network), data, multimedia, etc. to a telecommunications network. This system facilitates full voice, data, and fax utilization. This system is designed to replace existing local loops or provide infrastructure for those communities with no local loop in place. In this type of system a subscriber has a corresponding subscriber station and the central office (CO) has a corresponding base station.